The present invention relates to a system for controlling unbalance of the wash assembly in a vertical-rotation-axis washing machine.
More specifically, in the following description, the term “vertical-rotation-axis washing machine” refers to a washing machine comprising a wash drum rotated by an electric drive unit about a substantially vertical axis or about an axis tilted with respect to a vertical axis.
As is known, in vertical-rotation-axis washing machines, unbalance of the wash assembly caused by the load inside the drum must be determined continuously during the spin cycle to adequately control rotation of the drum in the event of excessive unbalance, which could result in the wash assembly colliding with the outer casing of, and so damaging, the washing machine.
In washing machines of the above type, steps must also be taken to reduce vibration and walk of the machine on the supporting surface during the spin cycle.
In currently marketed vertical-axis washing machines, the above drawbacks are partly solved by appropriately calibrating a number of operating parameters characteristic of the wash cycle. Given the large number of parameters involved, however, calibration is complex and does not entirely eliminate the risk of collision of the wash assembly, and/or vibration, and/or walk of the washing machine referred to above.